Intraaxonal injection of neurobiotin reveals the long-ranging projections of Aβ-hair follicle afferent fibers to the cat dorsal horn

Abstract

1. The morphology and somatotopic organization of the spinal arborizations of identified Aβ-hair follicle afferent fibers (HFAs) with receptive fields (RFs) on the digits have been investigated in the cat by the use of intraaxonal injection of the tracer n-(2 amino-ethyl) biotinamide. 2. In three cats, the long-ranging projections of six HFAs were examined by selectively injecting afferents with RFs on digit 2, 4, or 5, directly over the digit 3 representation, and examining their collateral morphology in transverse sections of the spinal cord. The rostral and caudal boundaries of the digit 3 representation were determined by mapping the RFs of identified spinocervical tract (SCT) neurons. 3..